Make your joystick playable with TI 99/4a Computer with Champ Adaptor.  Listed as No. 2 PC-310.

For use with:

Super Champ JC-250

Remote Champ RC-350

Mini Champ JC-351

And any other Atari 2600 compatible joystick

(One player only)

New old stock in original unopened packaging.  Untested, sold as-is.